ddr: altera: sdram: Clean up sdram_calculate_size() part 2

[karo-tx-uboot.git] / drivers / ddr / altera / sdram.c

diff --git a/drivers/ddr/altera/sdram.c b/drivers/ddr/altera/sdram.c
index b540c788edb7747d3a467057c41f7986f77d3208..45ae690edd15ad33e61e93b13b0384af9e0519da 100644 (file)
--- a/drivers/ddr/altera/sdram.c
+++ b/drivers/ddr/altera/sdram.c
@@ -451,14 +451,11 @@ int sdram_mmr_init_full(unsigned int sdr_phy_reg)
        return status;
 }
 
-/*
- * To calculate SDRAM device size based on SDRAM controller parameters.
- * Size is specified in bytes.
+/**
+ * sdram_calculate_size() - Calculate SDRAM size
  *
- * NOTE:
- * This function is compiled and linked into the preloader and
- * Uboot (there may be others). So if this function changes, the Preloader
- * and UBoot must be updated simultaneously.
+ * Calculate SDRAM device size based on SDRAM controller parameters.
+ * Size is specified in bytes.
  */
 unsigned long sdram_calculate_size(void)
 {
@@ -476,23 +473,17 @@ unsigned long sdram_calculate_size(void)
        col = (temp & SDR_CTRLGRP_DRAMADDRW_COLBITS_MASK) >>
                SDR_CTRLGRP_DRAMADDRW_COLBITS_LSB;
 
-       /* SDRAM Failure When Accessing Non-Existent Memory
+       /*
+        * SDRAM Failure When Accessing Non-Existent Memory
         * Use ROWBITS from Quartus/QSys to calculate SDRAM size
         * since the FB specifies we modify ROWBITs to work around SDRAM
         * controller issue.
-        *
-        * If the stored handoff value for rows is 0, it probably means
-        * the preloader is older than UBoot. Use the
-        * #define from the SOCEDS Tools per Crucible review
-        * uboot-socfpga-204. Note that this is not a supported
-        * configuration and is not tested. The customer
-        * should be using preloader and uboot built from the
-        * same tag.
         */
        row = readl(&sysmgr_regs->iswgrp_handoff[4]);
        if (row == 0)
                row = rowbits;
-       /* If the stored handoff value for rows is greater than
+       /*
+        * If the stored handoff value for rows is greater than
         * the field width in the sdr.dramaddrw register then
         * something is very wrong. Revert to using the the #define
         * value handed off by the SOCEDS tool chain instead of
@@ -504,18 +495,16 @@ unsigned long sdram_calculate_size(void)
        bank = (temp & SDR_CTRLGRP_DRAMADDRW_BANKBITS_MASK) >>
                SDR_CTRLGRP_DRAMADDRW_BANKBITS_LSB;
 
-       /* SDRAM Failure When Accessing Non-Existent Memory
+       /*
+        * SDRAM Failure When Accessing Non-Existent Memory
         * Use CSBITs from Quartus/QSys to calculate SDRAM size
         * since the FB specifies we modify CSBITs to work around SDRAM
         * controller issue.
         */
-       cs = (temp & SDR_CTRLGRP_DRAMADDRW_CSBITS_MASK) >>
-             SDR_CTRLGRP_DRAMADDRW_CSBITS_LSB;
-       cs += 1;
-
        cs = csbits;
 
        width = readl(&sdr_ctrl->dram_if_width);
+
        /* ECC would not be calculated as its not addressible */
        if (width == SDRAM_WIDTH_32BIT_WITH_ECC)
                width = 32;
@@ -526,7 +515,7 @@ unsigned long sdram_calculate_size(void)
        temp = 1 << (row + bank + col);
        temp = temp * cs * (width  / 8);
 
-       debug("sdram_calculate_memory returns %ld\n", temp);
+       debug("%s returns %ld\n", __func__, temp);
 
        return temp;
 }